EGFR mutation status and first-line treatment in patients with stage III/IV non-small cell lung cancer in Germany: an observational study.

Introduction: EGFR mutations confer sensitivity to EGFR tyrosine kinase inhibitors (TKI) in advanced non-small cell lung cancer (NSCLC). We investigated the clinicopathologic characteristics associated with EGFR mutations and their impact on real-world treatment decisions and outcomes in Caucasian patients with advanced NSCLC.

Methods: REASON (NCT00997230) was a noninterventional multicenter study in patients (≥18 years) with stage IIIb/IV NSCLC, who were candidates for EGFR mutation testing and first-line systemic treatment, but not eligible for surgery or radiotherapy. Patients were followed up according to normal clinical practice and assessed for primary (correlation of mutation status with baseline characteristics) and secondary endpoints (first-line treatment decision).

Results: Baseline data were obtained for 4,200 patients; 4,196 fulfilled the inclusion criteria; EGFR mutations were detected in 431 patients; no EGFR mutations were detected in 3,590 patients; mutation status was not evaluable in 175 patients. In multivariate analysis, the odds of EGFR mutations were significantly higher (P < 0.0001) in females versus males (odds ratio: 1.85; 95% confidence interval, 1.48-2.32), never-smokers versus smokers (3.64; 2.91-4.56), and patients with adenocarcinoma versus other histologic subtypes (2.94; 2.17-4.08). The most commonly prescribed first-line systemic treatments were: EGFR-TKIs in EGFR mutation-positive NSCLC (56.6%) and combination chemotherapy in EGFR mutation-negative NSCLC (78.5%).

Conclusions: This represents the largest dataset for EGFR mutations in Caucasian patients and shows EGFR mutations to be most prevalent in females with adenocarcinoma who had never smoked.

Impact: These findings add to our understanding of the prognostic and predictive factors of NSCLC, supporting future improved treatment selection.